Understanding the interplay between coxsackievirus and the host ubiquitin-proteasome system

了解柯萨奇病毒与宿主泛素蛋白酶体系统之间的相互作用

• 批准号: RGPIN-2016-03811
• 负责人: Luo, Honglin
• 金额: $ 3.21万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=708427
• 关键词: Understanding; interplay; between; coxsackievirus; host

Positive RNA viruses, which have all their genetic information in a single positive-strand of RNA, encompass more than one-third of all virus genera and cause various diseases in plants, animals, and humans. To ensure successful infection, viruses in this family have evolved to exploit the host cellular machinery, such as the ubiquitin-proteasome system (UPS), to support their lifecycle. The proteasome is a large cellular complex that breaks down unwanted or damaged proteins that have been marked with a small protein called ubiquitin. Apart from influencing the stability of the target proteins, attachment of ubiquitin can also change the function/activity of substrate proteins without targeting them for degradation. In this research program, we will use coxsackievirus as a model organism to understand how positive-strand RNA viruses interact with the host UPS to achieve successful production. Our hypothesis is that coxsackievirus subverts this system to support its infection by regulating the abundance and function of host and viral proteins. We previously discovered that depletion of ubiquitin or inhibition of the proteasome activity markedly reduces viral replication, suggesting an important role for the UPS in coxsackieviral infection. In addition, we found that ubiquitin-independent proteasome-mediated degradation is also utilized by coxsackievirus to promote viral growth. However, the exact mechanism of action has not been elucidated. Here we propose to study the molecular basis responsible for the dysregulation of the UPS as a consequence of coxsackievirus infection and the underlying mechanisms by that control viral replication. Specifically, we will combine the use of cutting-edge proteomics approaches with conventional molecular and cellular technologies to investigate how viral proteins manipulate the UPS and to identify the critical enzymes and target proteins within the UPS that regulate viral infectivity. We will also dissect out the functional significance of ubiquitin-mediated modification of viral proteins. This research explores a novel proteasome-based mechanism that will change our understanding of how viruses subvert the host cellular machinery. Knowledge gained from this program will also have broader implications for the study of host-pathogen interaction of other viruses in the same family.

阳性RNA病毒在单个阳性的RNA中具有所有遗传信息，包括所有病毒属的三分之一以上，并在植物，动物和人类中引起各种疾病。为了确保成功的感染，该家族的病毒已经发展为利用宿主细胞机制，例如泛素 - 蛋白酶体系统（UPS），以支持其生命周期。蛋白酶体是一种大型细胞复合物，可分解不需要或受损的蛋白质，该蛋白质被称为泛素的小蛋白质。除了影响靶蛋白的稳定性外，泛素的附着还可以改变底物蛋白的功能/活性，而无需靶向降解。在该研究计划中，我们将使用Coxsackievievirus作为模型生物体，以了解阳性链RNA病毒与宿主UPS的相互作用以实现成功生产。我们的假设是，Coxsackievivirus通过调节宿主和病毒蛋白的丰度和功能来颠覆该系统以支持其感染。我们先前发现，泛素枯竭或抑制蛋白酶体活性显着降低了病毒复制，这表明UPS在Coxsackievieviviviral感染中起着重要作用。此外，我们发现Coxsackievivirus还利用了与泛素非依赖性蛋白酶体介导的降解来促进病毒生长。但是，确切的作用机理尚未阐明。在这里，我们建议研究由于Coxsackievivirus感染和通过该控制病毒复制的基本机制而导致UPS调节失调的分子基础。具体而言，我们将使用最先进的蛋白质组学方法与常规分子和细胞技术相结合，以研究病毒蛋白如何操纵UPS并鉴定调节病毒感染性的UPS中的关键酶和靶蛋白。我们还将剖析泛素介导的病毒蛋白修饰的功能意义。这项研究探讨了一种新型基于蛋白酶体的机制，该机制将改变我们对病毒如何颠覆宿主细胞机械的理解。从该计划中获得的知识也将对同一家族中其他病毒的宿主病原体相互作用的研究具有更广泛的影响。